Carbureter.



tion.

UNITED STATES PATENT OFFICE.

ASHLEY C. BENNETQ OF MINNEAPOLIS, MINNESOTA.

CARBURETER.

Application filed. m 16, 1914. Serial No. 851,273.

To all "whom it may concern Be it -known that I, ASHLEY CBENNETT, acitizen of the United States, residing at: Minneapolis, in the county ofHennepin and State of Minnesota, have invented certain new and usefulImprovements in Carbureters, of which the following is a specifica- 'Myinvention relates to carburetors and has for its object to provide novelmeans for controlling the operation of the valve for admitting secondaryair and regulating the fuel admission.

It is the object of my invention to apply to. the valve-stem forsecondary air a dashpot construction with a small and controllableby-pass whereby the movement of the secondary air-valve will be steadiedand not fluctuate and jump.

The full objects and advantages of my invention will appear inconnectionwith the detailed description thereof-and are particularlypointed out in the claims.

The figure of the drawing, illustrating the application of my inventionin one form, comprises a sectional elevation view of a carbureterinvolving my improvements.

As illustrated, a casing 10 is formed with a fuel chamber 11 incommunication with asource of fuel supply 12 controlled by a floatvalveconstruction 13 of common form, the valve and fuel supply not beingshown. Directly connected with the chamber 11 is a dash-pot chamber 14formed of a supple mental casing extension 15 having a by-pass 16 in awall thereof, opening at 17 into chamber 14 and at 18 into chamber 11..By means of a screw 20 the opening 17 of the bypass may be increased ordiminished, as desired, for a purpose later to be explained. The chamber11 communicates through a passageway 21 with a feed casing 22 at thebottom of the carburetor mixing chamber 23 formed by casing and pipe 24,and the floatmeans of'a spring 31, said spring being positioned betweenthe bottom casing wall and a collar 32 on a valve-stem 33, which extendsthrough a cylindrical bearing or box ing 34 into chamber 11 and throughan enlarged aperture in float 13 to the top of chamber 14, where apiston 35 is secured to said valve-stem 33 and works freely but in closeengagement with the walls of chamber 14. Connected with valve-stem 33,through anextension 36 of collar 32, is an arm 37 which is pivoted at 38and has an arm 39 extending from said pivot into chamber 23 andcontrolling a needle valve 42, operable through feed pipe 40 forregulating the feed of fuel through duct 41 in feed casing 22.

Specification of Letters Patent. Patented June. 6, 1916. l

The carburetor operates in the following manner. At slow speeds primaryair is admitted through ports 43 in the casing 24 and fuel oil feedspast the .valve 42 and into the feed-pipe 40, frim which it dischargesthrough a multiplicity of openings 45 in the walls thereof, the valve 42being adjusted by hand screw 44' so as to admit gasolene at the desiredrate,at slow speeds. When the speed of the engine increases and theconsequent vacuum in chamber 23 and connected chamber 28 reaches thedesired degree, the pressure of the atmosphere upon valve 30, or

what is commonly designated as the suction passageway 17, the valve 30cannot jump,

downwardly under sudden increase of pressure, but must move slowly,owing to the time required for the trapped oil displaced to pass outthrough duct 16. when the vacuum falls in chamber 28' and the pressurerises, the piston 35 prevents the Conversely,

spring 31' causing the valve 30 to jump" quickly back into closingposition. It will be apparent, therefore, that with this constructionthe valve 30 is steadied in its operation and cannot, anddoes not,fluctuate.

The result is a much steadier flow of secondary air, more uniform mixingof air, and

less tendency to condensation in the manifold from pulsing changes ofvelocity of the combustion mixture.

I claim:

1. A carbureter comprising a casing formed with a fuel chamber and asecondary air passageway separate therefrom and positioned above thefuel chamber, and also having a dash-pot chamber opening directly fromthe bottom of the fuel chamber below the secondary air passageway, aduct or bypass being provided leading from the bottom of said dash-potchamber to the fuel chamber and an admission port for secondary airbeing provided, a valve spring-held to close said admission port, a stemattached to said valve and extending through the fuel chamber and intothe dash-pot, and a piston in the dash-pot on said valve stem.

2. A carbureter comprising a casing formed with a fuel chamber and asecondary air passageway separate {therefrom and posifive cents tionedabove the fuel chamber, and also hav mg a dash-pot chamber openingdirectly from. the bottom of the fuel chamber below the secondary airpassageway, a duct or by-pass being provided leading from the bottom ofsaid dash-pot chamber to the fuel chamber and an admission port forsecondary air being provided, a valve spring held to close saidadmission port, a stem attached to said valve and extending through thefuel chamher and into the dash-pot, a piston in the dash-pot on saidvalve stem, and means for controlling the extent of opening of the ductto vary the rate of movement of the piston in the dash-pot.

In testimony whereof I affix my signature in presence of two witnesses.

ASHLEY C. BENNETT.

Witnesses:

H. A. BowMAN, F. A. WHITELEY.

each, by addressing the Commissioner of Patents Washington, D. G.

